The ChangingMinds Blog!

How much evidence do you need? How do I know I am
a nice person?

We all need to think we are good people. Even criminals self-justify by
blaming their victims or believing themselves more deserving. But how much
evidence do we need? There is a whole spectrum of evidence requirement, although
perhaps we tend to cluster towards one or another end.

The exception that proves the rule

One way of seeking proof is to find just one bit of evidence. For example all
I need is to think about is one time I have been nice to someone, from which I
can conclude that I am a nice person. This is a strategy used by people who are
often unkind to others, but have a small circle of friends. In a position of
authority they are likely to have favorites, who are typically harmless people
who do as they are told.

This is of course a very unscientific method, where repeatable evidence is
needed for a conclusive proof. Yet many of us are affected by 'confirmation
bias' whereby we seek any evidence and quickly conclude our case is proven. This
happens in decision-making too, where we make a decision and then seek evidence
that justifies what we have already decided.

Falsification inversion

The reverse way of seeking evidence is also to depend on a single piece of
data, but now it is in the reverse sense. Now, all you need is a single piece of
evidence to disprove the rule. In the niceness stakes, this means that if you
are nasty to just one person, you are a nasty person, so you try to be nice to
everyone.

In science, Karl Popper defined this as falsification. For centuries, the
approach to science was to find 'enough' confirming evidence and then declaring
a general rule. The dilemma is that you cannot find evidence to prove very case,
so you just accept a common-sense body of confirming evidence. Popper got around
this by suggesting a double negative, whereby if you can devise a clever
experiment in which you aim to disprove the rule then one piece of evidence is
enough to prove that the opposite is true. Yes, it's tricky. The 'nice guy'
check would be to look for evidence that a person is nasty, and that not finding
this shows them to be nice.

Nice enough

Few of us are saints, and few are bad sinners either. We're not perfect, but
we try to be nice, which is what we want to think of ourselves. It is also what
we want others to think of us. So we are nasty only occasionally and mostly when
we can justify our unpleasantness.